Field of the Invention
The present invention relates generally to flash memories, and particularly to a flash memory device for storing critical or sensitive technical information and other data.
Discussion of the Known Art
Flash memories were developed from electronically erasable programmable read only memories (EEPROMs), and are used typically for storing programs and other non-volatile data for access and use by processors in the systems in which they reside. Flash memories may be of either a NAND or a NOR type, depending on the internal characteristics of the individual memory cells embedded in the memory. All or selected blocks of data stored in a flash memory can be electronically erased and reprogrammed. See, http://en.wikipedia.org/wiki/Flash_memory, and references cited therein.
If data to be stored in a flash memory is proprietary or sensitive, the data may need to be encrypted while at rest in the memory. For example, to comply with current anti-tamper (AT) requirements imposed by the United States Department of Defense (DoD) in DFARS 252.204-7012 (Nov. 18, 2013), contractors need to provide adequate security to safeguard unclassified controlled technical information (CTI) from being compromised. CTI is defined in the cited document as technical information with military or space application that is subject to controls on access, use, reproduction, modification, performance, display, release, disclosure, or dissemination of the information. See also DoD Instruction No. 5200.44 (Nov. 5, 2012).
Other proprietary applications may also require critical or sensitive software and data to be encrypted before the data is stored in a memory of a host system. In order to encrypt such software or data for storage in the memory, an outside cryptographic engine and associated processor must be added to the system. That is, hardware and software external to that originally embedded in the system are required for the encryption. These additional components, which may be contained in multiple enclosures, would need to be imposed between the flash memory and the host system processor that accesses the memory, thus complicating and slowing the overall encryption process.
Self-encrypting solid state disk drives are commercially available, for example, from Microsemi Corporation, Aliso Viejo, Calif., US. These devices are not part of an embedded system, however, and they require additional busses (e.g. SATA or USB) and software drivers to operate. As far as is known, however, flash memories that can be part of an embedded system and feature a self-encrypting function without special busses or drivers, have not been previously offered or disclosed.
Accordingly, there is a need for an embeddable flash memory device configured so that information or data stored in the memory is kept in an encrypted form while at rest in the memory, without the need for an external cryptographic engine and additional hardware and software.